American Society for Clinical Pathology (ASCP) Histotechnician Certification Practice Exam

Which profile requires patients to fast prior to testing?

1. Complete blood count

2. Lipid profile

3. Basic metabolic panel

4. Thyroid function tests

The correct answer is: Lipid profile

Fasting is a critical requirement for a lipid profile because the levels of certain lipids in the blood can be significantly affected by recent food intake. The lipid profile measures lipids such as cholesterol and triglycerides, and these measurements can show substantial variation after eating. When patients fast, it ensures that the levels measured are reflective of their true baseline levels, thus allowing for more accurate assessment of cardiovascular risk. In contrast, testing for a complete blood count, basic metabolic panel, and thyroid function tests typically does not require fasting. These tests can yield reliable results regardless of recent food consumption, as they focus on various blood components or metabolic functions that remain stable despite short-term dietary changes. The lipid profile's requirement for fasting is a specific protocol designed to enhance the reliability of cardiovascular risk assessments.